To safeguard biodiversity effectively, marine protected areas (MPAs) should be sited using the best available science. There are numerous ongoing United Nations and non-governmental initiatives to map globally important marine areas. The criteria used by those initiatives vary, resulting in contradictions in the areas identified as important.

This study analyzed how these initiatives overlay, quantified consensus, and conducted gap analyses at the global scale. By using the overlay map and data on current MPA coverage, the study also assessed gaps in protection of important areas of the ocean.

It was found that 55% of the ocean has been identified as important by one or more initiatives, and that individual areas have been identified by as many as seven overlapping initiatives.

The authors highlight that over 14% of the ocean fell into the category of moderate consensus (identified by 2-4 initiatives) and most of this area is not yet protected. The largest concentrations of moderate consensus areas without protection were found in the Caribbean Sea, Madagascar ant the southern tip of Africa, the Mediterranean Sea, and the Coral Triangle. While areas of high consensus (identified by 5-7 initiatives) were almost always within MPAs, but their no-take status was often unreported. The study underlines that nearly every marine province and nearly every exclusive economic zone contained area that has been identified as important but is not yet protected.

It is concluded that the results on areas of consensus provide initial insight into opportunities for further ocean protection.

Gownaris et al. (2019) Gaps in protection of important ocean areas: a spatial meta-analysis of ten global mapping initiatives. Frontiers in Marine Science doi: 10.3389/fmars.2019.00650